3.10 Declaration of the Receivers for Dewan UTeM 1 by using
CATT Software 21
3.11 Measurement setup for the Validation Experiment
22
3.12
SLM set in the experiment: a SLM is calibrated before used.
b SLM being put on 1.2m tripod stand
23
3.13 The points of Reverberation Time in Experiment
24 4.1
The Model of Dewan UTeM 1: a views from sides of the hall
b views from the floor of the hall
26
4.2 The Reverberation Time of Receivers in Dewan UTeM 1
27 4.3
The Optimum Reverberation Time Graph Depends on The Room Volume for 500Hz Octave Sound. [14]
27 4.4
The Experimental Reverberation Time of Dewan UTeM 1 29
4.5 The Clarity of Dewan UTeM 1
30 4.6
The Division of the Receivers in Dewan UTeM 1 30
4.7 The Early Energy Fraction of Dewan UTeM 1
31 4.8
Model of Dewan Besar UTeM: a views from the side of the hall
b views from the below of the hall
33
4.9 The Reverberation Time of Dewan Besar
34 4.10
The Reverberation Time for The Receiver That Be Sitting on Stage
35
4.11 The Distribution of Early Energy Fraction of Receiver That
Sit on Stage 36
4.12 Figure 4.12: The Distribution of Clarity in Dewan Besar
36
4.13 Figure 4.13: The Distribution of Early Energy Fraction in
Dewan Besar. 37
4.14 Soundboard Set on Dewan UTeM 1 Ceiling
38 4.15
The Acoustic Performance of Dewan Utem 1 with Soundboard as Absorber
39
4.16 Graph of Difference RT Before and After Soundboard
Installation 39
4.17 Carpet is attached on Dewan UTeM 1 Floor
40 4.18
The Acoustic Performance of Dewan UTeM 1 with Carpet as Absorber
40
4.19 Graph of Difference RT Before and After Carpet Installation
41 4.20
Nylon Cloth attached to hall ceiling 42
4.21 Result of attaching Nylon Cloth at the hall ceiling.
42 4.22
Figure 4.22: Glass Fence Attached on the Stage 43
4.23
Result of attaching Glass Fence on stage
43
LIST OF SYMBOLS
FIGURE TITLE
RT Reverberation Time
V Volume of Rooms in m
3
S Total surface area of room in m
2
Α Average of Coefficient of Material Absorption of the
room surfaces
Et Early Decay Time EDT
p
Impulse response
τ C
D Early Limit of Sound
Clarity Early Energy Fraction
CHAPTER 1
INTRODUCTION
1.1 BACKGROUND
A speech is a method of delivering messages, knowledge or lectures. In delivering a speech, most all the activities involve speech between the source deliver and the
receivers. While listening to a speech, a clear sound is a very important. Clear sound will directly affect the listener’s attention. According to Smaldino Crandell 1999, a
person who develops skills in poor acoustic environment may develop long-term speech comprehension problems.
In a classroom, as example, loud and noisy environment will tend to make the students loss focus and the interest to learn. The noise and reverberation is also can
inhibit the reading and spelling ability, behavior, attention, concentration and academic performance. Hence, classrooms and lecture halls are also important, often neglected, to
have a perfect acoustic performance to make sure the speech can be delivered smoothly and correctly.
In this research, the study of the acoustic performance of lecture halls will be the main part of the projects. To narrowing the research, two Seminar Halls in UTeM have
been chose to be the specimens. The halls are Dewan UTeM 1 and Dewan Besar UTeM. The materials of the walls, floors and tops of the halls are the main subject to be
examined in this study. This is because the reflection and refraction of sounds can be influenced by the materials used.
On the same time, most of the lecture halls, in huge or small size, are using reinforcement system. Reinforcement system is where combination of tools used to
make the sound can be heard in every side of the hall. Addition of tools like microphones, signal processors, amplifiers and loudspeakers will help to make the voice
louder. Sometimes, connection of too many reinforcement tools will bring the outputs of humming, buzzing, vibration and echoes. Hence, the factor of getting the clear sound is
neglected.
This study will helps on giving result of good acoustic performance in the way to give best decision for the architects to either choose the correct materials in building or
else, allocate absorbers in the right position.
1.2 PROBLEM STATEMENTS
Kategori